It is not a pant. A pant is only one part of it, hence why it is called a pair of pants. A pant is just one side, so please do not insist on finding me a pant that fits my shape as I want a pair of them sewn together. I realize this is big in the garment/fashion industry and that only bothers me more because it seems to me that it came about to make those saying it feel more refined. This may not be the case, they may have always called it a pant but it is only leaking out of the fashion/garment world recently, but that is still how I interpret it. I also just think it sounds stupid.
Meanwhile, the industry also adds unnecessary -ing to nouns. You don't buy sheets; you buy sheeting. Look at our lovely toweling. New, 100% cotton, no-iron shirting.
So when will they put the two trends together and offer us panting? 
Haha! I sure as shirting hope not.
That brings me around to another grammar thing that bothers me. "I am wanting" or "I am getting to" or "I am needing", et cetera. Why can't you just say "I want" or "I get to" or "I need"?
Well, depending on what context, the -ing construction should be used. For example:
She is wanting to see the play, but her father objects.
I am getting to the station around noon.
You are needing to buy a ship, yes? (This one's a bit stilted, I admit)
In other words, it's talking about an ongoing action in the present. I wouldn't use them when it would sound better to say wants/gets/needs, but they have their place in the language.